Proface GP4600R - 12.1 Standard HMIs with Rear Mounting Options" - Manual (Page 29)

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Wiring
3. Wiring Cautions
Improving Noise/Surge Resistance
•
The GP unit’s power supply cord should not be bundled with or kept close
to main circuit lines (high voltage, high current), power lines, or input/
output lines, and their various systems should be kept separate. When
power lines cannot be wired via a separate system, use shielded cables for
input/output lines.
• Make the power cord as short as possible, and be sure to twist the ends of
the wires together (i.e. twisted pair cabling) from close to the power supply
unit.
• If there is an excess amount of noise on the power supply line, connect a
noise reducing transistor before turning on the power.
• Connect a surge absorber to handle power surges. Be sure to ground the
surge absorber (E1) separately from the GP unit (E2).
Short Circuit Prevention
•
The SG (signal ground) and FG (functional ground) terminals are
connected internally in the GP unit. When connecting the SG line to
another device, be sure that no shorting loops are formed.
Grounding
•
Use an exclusive grounding wire with a grounding resistance of 100 Ω or
less and a wire of 2mm
2
(AWG 14) or thicker, or your country’s applicable
standard.
Lightening Surge Absorber
E1 E2
FG
GP
GP unit
Other
Equipment
Exclusive Grounding
(Best)
GP unit
Other
Equipment
GP unit
Other
Equipment
Common Grounding
(OK)
Common Grounding
(Not OK)